1. Field of the Invention
The invention relates to a composite granule comprising low-substituted hydroxypropyl cellulose bringing disintegrability or a binding property in production of the preparation for pharmaceuticals or food; and a rapid release preparation. The invention particularly relates to an orally fast disintegrating tablet excellent in a binding property and disintegrability.
2. Description of the Related Art
In recent years, there has been a demand for the development of orally fast disintegrating tablets which patients inferior in swallowing ability such as the elderly and children can take easily without water. For example, WO01/064190 discloses a method of preparing such tablets by forming a drug, a sugar and a water-soluble polymer such as polyvinyl alcohol into a shape in a wet state and then drying it.
There has also been a demand for the development of a method of preparing orally fast disintegrating tablets without using a special technology or special apparatus. Under such a circumstance, the dry direct tableting method comprising the steps of simply mixing a drug with an additive, adding a lubricant thereto for further mixing, and compressing the resulting mixture into tablets, is a highly productive method having neither a granulation step nor a drying step.
It is described in JP 2002-104956A that a base material for dry direct tableting is obtained by impregnating low-substituted hydroxypropyl cellulose with a sugar or sugar alcohol and then drying the resulting mixture. It is described in WO2011/019043 that an orally fast disintegrating tablet comprises a granule containing a drug, a water-soluble polymer such as polyvinyl alcohol, and a sugar alcohol; and spray-dried particles containing mannitol or mannitol and xylitol as a drug-free tableting base material, carboxymethyl cellulose, and a disintegrant such as low-substituted hydroxypropyl cellulose. A method of granulating a sugar or sugar alcohol while spraying thereto an aqueous dispersion of low-substituted hydroxypropyl cellulose is described in JP 2010-189384A.